Retrievable well packer



. 17, 1968 M. CROW ETAL RETRIEVABLE WELL PACKER 5 Sheets-Sheet 1 Filed June 27, 1966 INVENTORS Morgan L. Crow Marion D. Kil

gore Pumpelly R0 ert ATTORNEY E7, 1968 ML. CROW ETAL 3,416,608

RETRIEVABLE WELL PACKER Filed June 27, 1966 5 Sheets-Sheet 2 C 5 HA INVENTORS F 248 Morgan L.Crow

2 MorionOKHgore Robert C.Pumpelly 258 E1501 BY ATTOR KEY Dan. 17, 1968 M. L. CROW ETAL RETRIEVABLE WELL PACKER 3 Sheets-Sheet Filed June 27. 1966 Q- l OIL-A &

m Y m y. w V 8 H R a re 0 vw w mrMJm A L L C m O 8 Wflb O00 MM United States Patent 3,416,608 RETRIEVABLE WELL PACKER Morgan L. Crow, Marion D. Kilgore, and Robert C. Pumpelly, Dallas, Tex., assignors to Dresser Industries, Inc., Dallas, Tex., a corporation of Delaware Filed June 27, 1966, Ser. No. 560,756 8 Claims. (Cl. 166129) ABSTRACT OF THE DISCLOSURE A retrievable packer for use in a well bore. A mandrel extends through the packer and is coupled with a lower anchoring mechanism adapted when actuated to hold the packer against downward movement in the well bore. An upper anchoring mechanism for the packer includes a setting sleeve that is carried by the mandrel and arranged to engage segmented expanders which are in turn engaged by upper slips upon relative movement between the mandrel and the segmented expanders. The slips are moved radially by such engagement to retain the packer against upward movement in the well bore. A deformable packing element, located between the anchoring mechanisms, forms a fluid-tight seal with the well bore. Valve means is provided in the packer to control flow of fluid through a by-pass passageway located between the packing element and the mandrel.

This invention is concerned with a mechanically anchored retrievable well packer arranged to be anchored and set in the casing of a well and is particularly concerned with such a well packer which is anchored to hold against pressure from both above and below.

Among the objects of the invention are the following:

A mechanically anchored retrievable well packer which may be anchored to hold against pressure from both above and below.

A mechanically anchored retrievable well packer which has a fluid circulation passage therethrough between the packer rubber and the mandrel with seal means carried on the mandrel to close said passage when the packer is set.

Such a well packer which compensates for pressure fluctuations above and below same to provide a tighter seal between the packer rubber and the casing.

Such a packer construction wherein the slips and setting heads at each end thereof are positively held out of contact while the packer is being lowered to prevent premature setting of the packer.

Such a packer construction wherein the packer may be moved into setting position by a slight rotation of the tubing string.

A packer construction of the type indicated wherein an additional compression in the packing rubber and tension in the tubing string may be attained after the packer is set by a simple upward movement of the tubing string.

A packer construction of the type indicated which may be placed in retrievable position by simple rotation of the tubing string in the appropriate direction.

A packer construction of the type indicated wherein the tubing string may be set in tension, compression, or may be allowed to remain in neutral position, as elected.

A packer construction of the type indicated wherein the by-pass through the packer may be opened to permit circulation therethrough while the packer is set.

A packer construction of the type indicated wherein by simply reversing a J-slot body the J-slot therein may be reversed to thereby reverse the direction of rotation of the tubing required for setting and retrieving the packer.

A general object of the invention is to provide a simple, trouble-free, compact mechanically held, retrievable packer which is versatile in its operations for carrying out all completion and remedial operations in a well.

Summary of the invention The foregoing objects are accomplished by the inven tion which provides an improved packer for use in a well bore and includes: a tubular mandrel; packer support means surrounding the mandrel and releasably attached thereto; a packer sleeve encircling the mandrel in spaced relationship thereto; a resilient packing element disposed on the sleeve adapted to be deformed into sealing engagement with the wall of the well bore; ports above and below the sleeve providing a by-pass passage between the sleeve and mandrel; anchoring means disposed above and below the packing element arranged to be moved into holding engagement with the wall of the well bore; and seal means carried by the mandrel for engaging the sleeve to close the by-pass passage.

Other and further objects of the invention will become apparent upon reading the detailed specification hereinafter following and by referring to the drawings annexed hereto.

A suitable form of the invention is shown in the attached drawings wherein:

FIGS. I and IA are a quarter sectional elevational view of a preferred form of the packer as it would appear in unset condition;

FIG. II is a side elevational view of the J-slot employed with the preferred form of FIGS. I and IA;

FIGS. III and IIIA are a quarter sectional elevational view of a modified form of packer construction as it would appear in unset condition;

FIG. IV is a side elevational view of the I-slot employed with the modified form of FIGS. III and III-A;

FIGS. V and V-A are a quarter sectional elevational view of another modified form of packer construction as it would appear in an unset condition; and

FIG. V1 is a side elevational view of a J-slot employed with the form shown in FIGS. V and VA.

Numeral references are employed to indicate the various parts shown in the drawings and like numerals indicate like parts throughout the various figures of the drawings.

Description of form shown in FIGS. 1, IA and II Referring to the preferred form of FIGURES I and IA there is a top connection 1 which is adapted for connection to a tubular production string 1a by the threads 2 and for attachment to a mandrel 3 at the mating threads 4. The top connection 1 is further adapted for connection to a recovery ring 5 by the mating threads 6, said recovery ring 5 having an inwardly projecting portion at the lower end thereof providing an upwardly facing shoulder 7.

The mandrel 3 has an outwardly extending annular portion 8 which presents an upwardly facing shoulder 9 and which has a reduced diameter 10.

The mandrel 3 is further adapted for connection to a Islot body 11 at the companion threads 12.

A profile or slot 13 is milled, cast, or fabricated on the exterior surface of the ]-slot body 11 (see FIGURE II). The J-slot body 11 is adapted for connection to a lower tubular string 14a by the companion threads 14.

There is a settin sleeve 15 slidably arranged around the mandrel 3. The downward motion of sleeve 15 with respect to mandrel 3 is limited by the engagement of an outwardly extending portion 16 on the setting sleeve 15 with the upwardly facing shoulder 7 on the recovery ring 5. A slip take-up spring 17 is positioned between the upper end of the setting sleeve 15 and the lower end of the connection 1 and is encircled by the recovery ring 5.

The setting sleeve 15 has one or more longitudinal slots 18 provided through the wall thereof for the purpose hereinafter mentioned.

The setting sleeve is terminated at its lower end by a tapered surface 19.

A slip rest carries a pick-up pin 21 which is rigidly attached thereto by the companion threads 22. The slip rest 20 further includes a reduced diameter portion 23 encircling the setting sleeve 15 which is arranged to carry upper slip springs 24 thereabout and to limit the inward travel of a multiplicity of upper toothed slips 25 when said upper slips are in a retracted or relaxed position. An upper slip housing 26 is attached to the slip rest 20 by the mating threads 27 and has a multiplicity of open-ended T-slots 28 formed through the wall thereof.

The upper slips 25 are suspended by the open-ended T-slots 28 by an outwardly projecting portion 29 which prohibits axial motion of the upper slips 25 with relation to the upper slip housing 26, but allows radial motion therebetween.

The upper slips 25 have toothed serrations 30 on the outer periphery thereof adapted for penetrating engagement with the inner wall of a casing when the packer is in an operating or set position. An outwardly and downwardly tapered surface 31 is adapted for engagement and co-action with an upwardly and inwardly tapered surface 32 on a multiplicity of upper head expander segments 33.

The upper head expander segments 33 are carried in a collapsed position around the mandrel 3 and urged thereto by a spring 34 encircling same. Downwardly depending portion 35 has a downwardly facing end 36 and threaded bores 37 by which segment retainer screws 38 are afiixed to each of the said upper head segments 33.

The downwardly facing ends 36 of the upper head segments 33 abut an inwardly extending portion 39 on a head cage 40 which is supported by the upwardly facing shoul der 9 of the outwardly extending portion 8 of mandrel 3. The head cage 40 has a multiplicity of bores 41 through the wall thereof adapted to receive the segment retainer screws 38 and co-acting therewith to position the upper head segments 33 to permit radial movement and to prevent axial movement in respect to head cage 40. The head cage 40 has a counterbore 42 therein which allows radial motion of the upper head segments 33 in respect to head cage 40.

The head cage 40 has threads 43 therein adapted for rigid attachment of a packing sleeve 44 around which is carried a resilient packing element 45.

The packing element 45 can be any of many configurations. It may be of a one piece elastic sleeve or of multiple segments 45a of elastic material (as shown), spaced by metallic rings 45b, or it may be specifically designed for high temperature application, or of a composition designed to be efficient in any of numerous environmental surroundings.

The head cage 40 also has a multiplicity of circulation ports 40a formed through the wall thereof.

The packing sleeve 44 has a reduced sealing bore 46 adapted for sealing engagement with a mandrel seal assembly consisting of a mandrel seal body 47, a mandrel seal 48, of resilient composition, and an inner sealing O-ring 49. The mandrel seal assembly is carried by the mandrel 3 in a fixed position between the reduced portion 10 of the outwardl extending portion 8 of mandrel 3 and a mandrel seal lock ring 50 carried in the groove 10a about the mandrel 3. The mandrel seal body 47 has a downwardly facing tapered surface 51 thereon which coacts with an upwardly facing tapered surface 52 in the packing sleeve 44 to transfer downward forces due to weight or compression of the upper tubular string In from the mandrel 3 to the packing sleeve 44 and thence to the entire packer assembly. The packing sleeve 44 further has an outwardly extending portion 53 adapted for coaction with a lower thimble 54 having mating threads 55 thereon for rigid attachment thereto of a lower expander head 56.

The lower expander head 56 has circulation ports 57 through the wall thereof, a counterbore 58, and an inwardly extending portion 59 which presents an upwardly facing shoulder 60. There is a downwardly and inwardly facing taper 61 on the outer surface of the lower head 56.

A multiplicity of lower slips 62 have upwardly and outwardly facing tapers 63 therein adapted for co-action, when set, with the taper 61 on the lower head 56 to expand the slips to cause outer teeth 64 to penetrate the casing wall. The slips have outwardly projecting portions 65 thereon which are carried in open-ended T-shaped slots 66 formed in a lower slip housing 67 in non-rotatable, non-axial movement with relation thereto, but which allows radial movement of the slips relative to said lower slip housing 67. The lower slip springs 68 are carried in the lower slip housing 67 and are adapted to urge the lower slips 62 into a retracted position. The lower slip housing 67 is rigidly attached to an anchor cage 69 by the mating threads 70. The anchor cage 69 carries a multiplicity of friction pads 71 in slots 72 formed in the wall of the anchor cage. Friction pads 71 are urged outwardly into frictional engagement with a casing by a multiplicity of friction pad springs 73 positioned therebehind.

The anchor cage 69 carries a gudgeon pin 74 attached rigidly in the wall thereof by the mating threads 75. Pin 74 extends inwardly through a hole 77 through the wall of recovery sleeve 76 and extends into engagement with the profile or slot 13 (FIGURE I-A) of the I-slot body 11.

The recovery sleeve 76 extends above the hole 77 therein and supports thereabout the friction pad springs 73 and the lower slip springs 68. Furthermore, the recovery sleeve 76 has an outwardly extended portion 78 at the upper end thereof which is adapted to contact the upwardly facing internal shoulder 60 of the lower head 56 to limit the relative axial movement therebetween.

Operation of form shown in FIGS. I, I-A and II Referring to FIGURES I and IA, the packer is shown in the running-in position except that the gudgeon pin 74 assumes a position 74a as shown in FIGURE II.

The packer is attached to the tubular production string 1a by the threads 2. Accessories, as required by the particular installation, are suspended to the packer by the lower threads 14.

The anchor cage 69, the lower slip housing 67, and the lower slips 62, urged into a collapsed position by the lower slip springs 68, are led into the hole by the gudgeon pin 74 in position 74a. Likewise, the recovery sleeve 76 is pulled into the hole by the gudgeon pin 74, and the outwardly extending portion 78 of the recovery sleeve 76, acting against the upwardly facing shoulder 60 of the lower head 56, pulls the lower head 56 and lower thimble 54 into the hole. Contact between the lower thimble 54 and the outwardly extending portion 53 of the packing sleeve 44 similarly leads the elements thereabove into the hole. The head cage 40, being attached to the packing sleeve 44 at the mating threads 43, is also led into the hole.

The upper head expander segments 33, are in a collapsed position and are urged inwardly by the head segment spring 34, and carried into the hole by inter-engagement of the segment retainer screws 38 in the holes 41 of the head cage 40.

The setting sleeve 15 is urged into extended position by the slip take-up spring 17 and is carried into the hole by the mandrel 3 with the pick-up pins 21 in the slip rest 20 engaging the slot 18 of the setting sleeve 15. The upper slips 25 are carried into the hole in a collapsed position and are maintained in collapsed position by the upper springs 24 engaged therewith.

It will be noted that, except for a minor possible movement represented by the difference between positions 74a and 74b in profile slot 13, the entire packer mechanism is carried into the hole in a rigidly connected extended position between the engagement of the gudgeon pin 74 in position 74a and the inwardly extending portion 39 of the head cage 40 resting on the upwardly facing shoulder 9 of the outwardly extended portion 8 of the mandrel 3. The upper slips 25 and associated structures are limited in downward telescoping movement by the recovery ring 5 attached to the top connection 1. There are positive gaps between the tapered surfaces 31 of the upper slips 2S and tapered surfaces 32 of the upper expander head segments 33, and the tapered surfaces 63 of the lower slips 62 and the surface 61 of the lower expander head 56. The limited movement permitted by positions 74a (running position) and 74b (retrieving position) of gudgeon pin 74 in slot 13 cannot close either of the gaps.

It should also be noted that turbulent fluid flow due to excessive running-in speed or the presence of foreign ob ects, such as scrap metal, sand, etc., cannot cause any element of this packer structure to move upwardly into premature setting position.

it will be noted also that in the unset or running-in position as shown in FIGURES I and IA, there is an unrestricted and adequate bypass of fluid through the ports 57 in lower head 56 and, through the sealing bore 46 of the packing sleeve 44, outwardly into the casing annulus through the ports 49:: in the head cage 40. Inasmuch as all elements are locked rigidly in unset position, this circulation passageway cannot be inadvertently closed or pumped closed due to movement of any ele ment under excessive speed of running-in or fluid velocity created by the circulation process.

The setting procedure has also been simplified by the construction, as follows:

When setting depth has been reached, a slight upward movement of the tubing string places the gudgeon pin 74 in the position 74b. Rotation to the right of the tubing string simultaneously with a lowering of the tubing string will place the gudgeon pin 74 in position 740 where a slight rotation to the left of the tubing string will allow the gudgeon pin to assume the position 74d or 74e. While the downward motion of the tubing string has been occurring, the anchor cage and lower slip assemblies are held immovable in respect to the casing by the friction pads 71, and the lower slips 62 and their tapered surface 63 have contacted the lower head 56 and the corresponding tapered surface 61. The lower slips 62 are thereby forced outwardly into engagement with the casing.

Simultaneously, the downwardly facing taper 19 of the setting sleeve has been forced into engagement with the upwardly facing tapers 33:: on the upper head expander segments 33, and has been forced underneath said upper head segments 33, causing them to expand outwardly to setting position. The upper slips through engagement of their tapered surface 31 with the tapered surfaces 32 of the upper head segments 33 are forced downwardly and outwardly into engagement with the casing wall. Further downward movement of the mandrel assembly to the position 74d of gudgeon pin 74 will move the mandrel seal 48 into sealing engagement with the seal bore 46 in the packing sleeve '44 and ultimate contact will be made between the downwardly facing surface 51 of the mandrel seal body 47 and the upwardly facing tapered surface 52 of the packing sleeve 44. Additional downward movement of the mandrel assembly will result in a compressive force being applied to the packing element 45 and the upper slips 25 will be ratcheted downwardly by the expansive force of the slip take-up spring 17. This maintains the upper slips 25 in a position to immediately engage and anchor against the casing to prevent upward movement upon relaxation of the downward force or reversal of the downward motion.

In installations where there is adequate tubing weight available to give the degree of compression on the packing element 45 required, the packer is now in a set position with the bypass tightly closed by the mandrel seal 48 in the lower portion of the seal bore 46 of the packing sleeve 44.

However, when the packer is set in relatively shallow holes, where adequate tubing Weight is not present, or under design considerations where tension in the tubing string is desired, the packer can be set in tension. The necessary tension can be obtained by lifting the tubing string. Upward movement of the tubing string causes the gudgeon pin 74 to assume the tension position 74e in profile slot 13 (FIGURE II), Further upward movement of the tubing places the tubing in tension and adds further compressive forces to the packing element 45. When the gudgeon pin 74 is in position 742, the mandrel seal 48 has been moved up but remains in sealing engagement with the upper portion of the sealing bore 46 in the packing sleeve 44 to maintain the by-pass closed.

Release and retrieval of the packer is simply and efiiciently performed as follows:

If the gudgeon pin 74 is in position 74d in Profile 13 of the l-slot body 11, a simultaneous pick-up of the tubing string and right hand rotation thereof will result in the gudgeon pin being placed in position 740. If the gudgeon pin is originally in position 74e, simple right hand rotation will likewise place it in the position 740.

Further upward movement of the tubing string and mandrel assembly will result in movement of the gudgeon pin 74 to retrieval position 74b in profile slot 13.

Concurrently with this upward motion of the tubing string, the setting sleeve 15 will be picked up by engagement of the shoulder 7 on the recovery ring 5 with the outwardly extending portion 16 on the setting sleeve 15 and removed from behind the upper head segments 33, allowing the upper head segments to collapse inwardly, removing the upper slips 25 from engagement with the casing. Then the pick-up pin 21 in the slip rest 20 will engage the lower end of slot 18 and the upper slip housing 26 and slip rest 20 will be moved upwardly. This results in the upper slips 25 being removed from any possibility of re-engagement with the upper head segments 33 which would cause setting of the slips and difficulty in the retrieving cycle.

The upward movement of the tubing string and mandrel assembly also moves the mandrel seal 48 upwardly out of engagement with the sealing bore 46 of the packing sleeve 44, and allows pressure equalization across the packing element and by-pass of fluid.

Ultimately, the shoulder 9 on the outwardly extended portion 10 of the mandrel 3 will engage and transfer the pick-up force to the inwardly extending portion 39 of the head cage 49. Further upward motion will cause the outwardly extending portion 53 of the packing sleeve 44 to engage the lower thimble 54 and by virtue of engaging threads 55 will move the lower head 56 up out of engagement with the lower slips 62. This motion also results in room for the packing element 45 to relax out of sealing engagement with the casing.

Engagement of the inwardly extending portion 59 on the lower head 56 with the outwardly extending portion 78 on the recovery sleeve 76 will result in a pick-up of the anchor cage 69 and the rigidly attached lower slip housing 67 which carries the lower slips 62 in collapsed position due to the inward urging of slip springs. This is accomplished by virtue of the co-action of the hole 77 in the recovery sleeve 76 with the gudgeon pin 74 extending therethrough and being threadably engaged with the anchor cage 69.

It should be noted that in the retrieving position, the packing element 45 has been provided room for relaxation, the circulation passageway has been opened, the non-engagement gaps between the upper slips and the upper head segment and the lower slips and lower head segments have been re-established and the several elements of the packer assembly have been locked in extended position between the outwardly extending portion 8 of the mandrel 3 and the gudgeon pin 74, now in position 74b in the profile 13 (FIGURE II).

Description of form FIGURE III, III-A and IV In the modified form shown in FIG. III, IIIA and IV, common elements and functional portions thereof are given the same numeral references as in FIG. I and IA and the physical and functional description of said elements are found in the description of FIG. I and I-A.

The upper top connection 1, the recovery ring 5, the slip take-up spring 17, the setting sleeve 15, the slip rest 20, the pick-up pin 21, the upper slip spring 24, the upper slip housing 26, the upper slips 25, the upper expander segments 33, and the segment retainer screws 38, are all functional portions of the modified form as described herein.

A mandrel 203 is attached to the top connection 1 by the mating threads 4 and extends downwardly through the packer assembly. The mandrel has an outwardly extending shoulder 8 and is connected by the mating threads 12 to a tubular J-slot body 211.

A profile or slot 213 is milled, cast or fabricated on the exterior surface of the J-slot body 211 (FIG. IV) and is adapted for connection to a lower tubular string 14a by the tubing threads 14.

A head cage 240, has an inwardly extending portion 39, against which the upper expander head segments 33 abut. There is also a multiplicity of lateral bores 41 provided through the wall of head cage 240 and said cage has a counterbore 42 therein.

The head cage 240 is further adapted by the mating threads 241 for rigid attachment to tubular valve housing 242. Valve housing 242 has equalizing ports 243 through the wall thereof at the upper end thereof, and circulation ports 244 through the wall thereof near the lower end thereof. The lower portion of the valve housing 242 has a primary reduced sealing bore 245 therein and a secondary sealing bore 246 in the upper portion thereof. The seal housing 242 is rigidly attached to a seal support ring 247 by the companion threads 248.

A mandrel seal body 249 is secured in non-sealing engagement around the mandrel 203. The mandrel seal body 249 has an undercut portion 250 thereon adapted to receive the outwardly extending annular shoulder 8 of the mandrel 203 and is rigidly locked thereto by a snap ring 251 carried in an appropriate groove provided in the wall of body 249. The mandrel seal body 249 further carries on its lower end a primary face seal 252 composed of elastic sealing material which may be molded rigidly therewith, or it may be adapted for replacement, as required. The mandrel seal body 249 also carries thereabout a secondary peripheral seal 253 composed of resilient material which may be moulded thereto or may be snapped into place in the groove in which it is carried for replacement, to engage the primary seal bore 245 of the seal housing 242 when the mandrel 203 is lowered relative to said seal housing 242 when the packer is set as hereinafter described.

The seal support ring 247 has an upwardly protruding annular valve seat 254 on the upper end which is adapted to sealingly engage the primary face seal 252 when the mandrel has been lowered relative to the seal housing 242, as will be described hereinatfer.

When the packer is in the running or retrieving position, as shown in FIGS. III and IIIA there is a floating piston 255 carried around the mandrel 203 and above the mandrel seal body 249. The floating piston 255 is adapted for slidable sealing engagement with the mandrel 203 by the resilient O-ring 256, carried in an appropriate groove on the inner side thereof, and for slidable sealing engagement with the secondary sealing bore 246 of the seal housing 242 by the resilient O-ring 257, carried in an appropriate groove thereabout.

The seal support ring 247 is adapted to apply a compressive force on a packing element, indicated generally as 45, and is rigidly attached to a packing sleeve 258 by the mating threads 43. The packing element, as shown, is made up of alternate resilient rings 45a and rigid rings 45b. An annular communication passageway 259 is formed by the interior bore of the packing sleeve 258 and the outer diameter of the mandrel 203. The passage 259 is open when the mandrel seal body 249 and the mandrel 203 are in the upper position, as shown in FIGS. III and III-A but is closed when the primary face seal 252 engages the annular valve seat 254 of seal support ring 247.

The packing sleeve 258 has an outwardly extending portion 253 engageable with support member 54, the function of which is described in connection with similar structure in FIGS. I and I-A.

The lower expander head 56 is connected by threads 55 to the support members 54 and associated lower slip and anchor structures are carried on the exterior of the I-slot body 211, all as previously described in the embodiment shown in FIGS. I and IA.

Operation of form shown in FIGURES III, III-A and IV Following is a description of the operation of the modified form of FIGURES III, III-A and IV.

The packer is made up on the upper production tubing 1a by the threads 2, as usual, and the necessary accessories, required by the particular installation are suspended below the packer by the threads 14.

In the running cycle, the gudgeon pin 74 is in position 74a, as shown in FIGURE IV. It should be noted that the entire packer assembly is held in an extended unset condition similar to that of the embodiment described in relation to FIGURES I and I-A, between the gudgeon pin 74- in position 74a in slot 213 and the inwardly extended shoulder 39 of the head cage 240 which is arranged to abut the floating piston 255, which in turn is arranged to abut the mandrel seal body 249. The mandrel seal body 249 is locked in a non-movable position with relation to the mandrel of 203 by the snap ring 251. The upper slips 25 and associated structures are held in an inward position out of engagement with the casing by the pick-up pin 21 disposed in the lower portion of the slot 18 in the wall of the setting sleeve 15, which is in its maximum downward position due to the engagement of outwardly extending portion 16 of setting sleeve 15 and the upwardly facing shoulder 7 of the recovery ring 5.

When the predetermined depth in the well for setting has been reached, the upper tubing string 1a, the mandrel 203 and J-slot body 211 are rotated. to the left to place the gudgeon pin 74 in position 74b (FIG. IV). The tubing string, mandrel 203, and ]-slot body 211 can now be lowered to set the packer exactly as previously described in connection with the embodiment shown in FIGURES I and I-A. The gudgeon pin 74 assumes a position approximately at 740 when the packer is set.

The differences in structure and function of this modified embodiment contrasted to the first embodiment described are as follows:

The primary face seal 252 and the secondary peripheral seal 253, carried by the mandrel seal body 249 are rigidly attached to the mandrel 203 and are free for reciprocal motion inside of the valve housing 242. The primary face seal 252 may move downwardly and contact the valve seat 254 which, co-acting therewith, establishes a fluid tight relationship therebetween when the weight of the tubing string is applied. Simultaneously, the sec ondary peripheral seal 253 enters into and engages the primary reduced seal bore 245 of the valve housing 242 in fluid tight relationship. Since the mandrel seal body 249, with the primary face seal 252 and the secondary peripheral seal 253, is carried in non-sealing engagement around the mandrel 203, the pressures encountered from below the packer will be communicated through said nonsealing engagement and will reflect downwardly on the area determined by the difference in areas of the seal bore 245 and the valve seat 254, thereby creating a downwardly acting force due to the pressure underneath the packer which holds the mandrel and its rigidly attached mandrel seal assembly in sealing engagement and effectively blocks circulation through the circulation ports 244. The pressure from beneath the packer which establishes this balanced valve mechanism comes through the ports 57 in the lower head 56 and is carried upwardly through the interior of the packing element 45 through the communication passageway 259 defined by the interior bore of the packing sleeve 258. This action, by proper selection of the two respective diameters, effectively creates an over balanced pressure which generates a downward force maintaining a fluid tight seal regardless of the magnitude of the pressure underneath the packer.

The floating piston 255 with its asociated O-rings 256 and 257 reacts to the direction of the differential in pressure existing between the annulus below the packer and the annulus above the packer. When the pressure below the packer is greater than the pressure above the packer the floating piston 255 remains in the upper position and effectively seals against communication from below the packer with the pressure outside of the packer through the equalizing ports 243. The force generated by the differential against the floating piston will be resisted by the inwardly extending portion 39 of the head cage 240 and transferred into the casing through the upper head segments 32 and slips 25 when the packer is set. However, when the pressure above the packer is greater than the pressure below the packer, the floating piston 255 will be moved downwardly against the mandrel seal body 249, still effectively blocking communication through the equalizing port 243 with the area below the seal and at the same time exerts a downward force on the mandrel seal body 249 which is transferred to the mandrel 263 through the snap ring 251 and shoulder 8 on the mandrel 203.

The foregoing describes the running and operation of the packer by this modified embodiment under usual conditions.

However, there are times, dependent on the actuation and function of accessory tools run below when right hand rotation offers the most efiicient and useful method of actuating the setting mechanism. By virtue of the C shape profile slot 213 in J-slot body 211, the body 211 may be reversed to permit setting by right hand rotation. To permit reversal of body 211 the threads 14 must be made as box threads identical with the mating threads 12. With the body 211 constructed in this manner, reversal of direction in the actuating rotation of the tubing string can be accomplished by simply removing the .T-slot body 211, inverting the body 211 and reassembling it with the mandrel 203. Right hand rotation of the tubular string and the mandrel assembly will then actuate the packer and place it in position for setting, as above described.

Retrieval of the packer for reworking or for other purpose, is obtained by simple upward pull on the production string and the mandrel assembly. The mandrel seal body 249, and its associated seals, is pulled upwardly out of sealing engagement with the valve seat 254 and the force of said upward pull is transmitted through the floating piston 255 into the inwardly extending portion 39 of the head cage 240. The upper slips and associated assemblies are moved up free of the expander heads 33 by the slot 18 in setting sleeve 15 contacting the pin 21 as described in the operation of the preferred embodiment, shown in FIGURES I and I-A, and all associated structures are retrieved from the hole as hereinbefore described. When the lower head 56 has been picked up and moved from beneath the lower slips 62, said lower slips, lower slip housing 67, anchor cage 69, and connected parts are brought out of the hole suspended on the gudgeon pin 74 in position 74b or, after appropriate rotation of the tubing string, in the position 74a (FIG. IV).

Description 0 form shown in FIGURES V, VA, and VI A description of the modified form shown in FIGS. V, V-A and V1 is as follows:

An upper connection 301 is adapted for connection to an upper tubing string 1a by the threads 2 and is further adapted for connection to the mandrel 303 by the mating threads 4.

The mandrel 303 has a section of reduced diameter 305 terminated by an upwardly facing shoulder 366. An enlarged annular portion 8 on the mandrel 303 presents an upwardly facing shoulder 9. A snap ring groove 10a is provided in mandrel 303 in which a snap ring 50 is disposed for the purpose hereinafter mentioned. The mating threads 12 are adapted for connection to a J-slot body 311. The outer surface of the ]-slot body 311 is milled to provide a I-slot profile or slot 313 (see FIG. VI) and has threads 14 thereon adapted to connect the packer to a lower production string 14a.

A setting sleeve 316 has a counterbore 317 therein terminating in an upwardly facing shoulder 318 at the lower end thereof and a tapered surface 319 at the upper end thereof. There is also an outwardly extending flange 321 at the upper end of sleeve 316 and a reduced diameter portion 321 thereon having one or more milled slots 322 formed therein. The sleeve 316 terminates in a tapered surface 323 at the lower end thereof. A slip rest 324 has an upwardly extending shell-like portion 325. The upwardly extending shell-like portion 325 of the slip rest 324 has an interiorly cut annular groove to receive a slip spring snap ring 326, which retains therein a spring stop ring 327 which retains therein a take-up spring 328. Said take-up spring 328 rests on a shoulder in the slip rest 324. The slip rest 324 has one or more lateral bores 329 in the wall thereof adapted to receive one or more pick-up pins 330 which are retained in the slip rest 324 by a snap ring 331 positioned in an appropriate groove. The pickup pins 330 extend through the slip rest 324 and are located in the slots 322 in the wall of setting sleeve 316.

The slip rest 324 has a depending portion 332 which is adapted to give interior support to a multiplicity of upper slips 25 and a like number of upper slip springs 24. The upper slip housing 26 depends from the slip rest 324 and is attached thereto by the mating threads 27.

The slip rest 324 also carries one or more shear pins 333 attached rigidly thereto by the mating threads 334 and extending into matching holes 335 in the wall of setting sleeve 316. The axial position established between the slip rest 324 and the setting sleeve 316 by the shear pins 333 is such that the pick-up pins 330 are initially located in the medial portion of the slots 322 in the setting sleeve 316. Such is a temporary position and exists only in the original running-in position and set position. When the packer is set as hereinafter described and the shear pins 333 are sheared, they serve no further useful function.

The description and function of the upper slip housing 26, the upper slip segments 25, the slip springs 24, the upper head segments 33, the segment retainer screws 38, are identical to the function of said parts heretofore described in previous embodiments.

The head cage 240 is identical in structure and function to the head cage 240 shown in FIGURE III and similar in function but different in structure from the head cage 40 shown in FIGURE I, heretofore described.

A spacer collar 341 has a multiplicity of circulation ports 342 through the wall thereof, and is attached at the upper end to the head cage 240 by the mating threads 43, and at the lower end to an upper thimble 343 by the mating threads 344. The upper packing support thimble 343 has an upwardly extending portion 345 and a lower face 346 adapted to apply compressive force to a resilient packing element 347. The packing element may be of standard construction, as is well known in the art, or of special construction for high temperature application (as shown), and has packer retaining rings 348 at each end thereof.

The packing element 347 is carried by and supported about a packing sleeve 349 having an outwardly extending annular portion 350 adapted for engagement with the upwardly extending portion 345 of the upper thimble 343. The packing sleeve 349 also has a sealing bore 351 on the interior thereof and is connected to a lower thimble 352 by the mating threads 353.

The lower packer support thimble 352 has an inwardly extending annular portion 354 therein and is attached by the mating threads 55 to the lower expander head 56.

The lower expander head 56 encircles the J-slot body 311, and associated structures are carried on the exterior of the J-slot body 311, all as previously described in the embodiment shown in FIGURES I and IA.

A resilient mandrel seal assembly 355 is carried about the mandrel 303 between the outwardly extending annular portion 8 and the snap ring 50. The mandrel seal assembly is adapted, when the mandrel is lowered in relation to the packing sleeve 349, to come into sealing engagement with the seal bore 351 of the packing sleeve 349. When high temperature conditions are expected, the mandrel seal assembly 355 is constructed of rings of thermal packing 356 positioned between spacers 357 at each end thereof. When normal temperature ranges are expected, the mandrel seal assembly can be identical with that shown in FIGURE 1.

Operation form shown in FIGURES V, V-A and VI The embodiment shown in FIGURES V and VA and VI is fixedly attached to the tubular production string 1a by the tubular threads 2. Any tubing, tail pipe, tools, etc., necessary for the particular installation design are carried below the packer by the threads 14.

With the friction pads 71 in frictional engagement with the casing (not shown), the anchor cage 69 and lower slips 62 are led into the hole as the tubing string is lowered. Note that there is a gap between the lower slips 62 and the lower expander head 56 which would still exist although the gudgeon pin 74 assumes the position 740 in the ]-slot profile 313.

The recovery sleeve 76, being fixed to the anchor cage 69 by the gudgeon pin 74 which extend through of the hole 77, is similarly led into the hole. Engagement of the outwardly extended portion 78 on the sleeve 76 with the shoulder 60 on the lower head 56, leads lower head 56, the lower thimble 352, the packing sleeve 349 and the packing element 347 into the hole. The outwardly extended shoulder 350 on the packing sleeve 349 abuts the upwardly extended portion 345 of the upper thimble 343 and leads the upper thimble 343, the spacer collar 341, and the head cage 240 into the hole. Connection of the segment retainer screws 38 with the upper expander head segments 33 and the engagement of the screws 38 with the head cage 240 pulls the segments 33 into the hole.

The upper slips 25, the upper slip housing 26, the slip rest 324, settting sleeve 316 and pick-up pins 330 are carried into the hole on the mandrel 303 between the shoulder 306 on the mandrel 303 and the upper connection 301.

The upper slip assembly including the slip rest 324 and the upper slips 25 are disengagably held in the position shown in FIG. V by the shear pin 333 protruding into the hole 335 in the setting sleeve 316. This arrangement remains during the original running-in operation, but the shear pin 333 is sheared when the packer is set.

It may be seen from the above that unintentional setting cannot occur during running-in since the lower slips 62 and head 56 are held in an extended position between the pin 74 and the annular portion 8 on the mandrel 303. The upper slips 25 are held in an extended position relative to segments 33 by contact of the shoulder 306 with the lower end of the sleeve 316. The only collapsing movement possible is a relatively small movement represented by the difference in the positions 7411 and 74b of gudgeon pin 74 in I-slot profile 313 (FIG- URE VI).

When the predetermined vertical position of the packer in the well bore has been reached, the tubing string, carrying the J-slot body 311, is picked up slightly moving pin 74 to position 74b. The tubing string is then simultaneously rotated clockwise and lowered to place the gudgeon pin 74 in position 740 in the J-slot profile 313. The tubing, mandrel, and ]-slot body can then be lowered through the exterior parts of the packer which are held in relatively non-movable position by the friction pads 71 in engagement with the casing.

Further downward movement of the tubing and associated assemblies will result in the following:

The lower expander head 56 will be lowered until the tapered surfaces 61 thereof comes in contact with tapered surface 63 of the lower slips 62, causing outward expansion of lower slips into engagement with the casing. Further downward movement will result in engagement of the tapered surfaces 323 of setting sleeve 316 with the tapered surface 33a in the upper head segments 33. Further downward movement of the mandrel 303 will cause the upper connection 301 to enter the counterbore 317 of the setting sleeve 316 and apply downward force on the setting sleeve 316 by contact between the upper connection 301 and the upwardly facing shoulder 318 of the setting sleeve 316. This will cause the setting sleeve 316 to be inserted behind the upper head segments 33 causing them to expand radially. After the segments 33 are expanded, the inner surfaces 31 on the upper slips 25 engage the tapered surfaces 32 on the segments, placing the upper slips 25 in position for engagement with the casing. Further force of downward movement will be transferred from the setting sleeve 316 to the inwardly extended portion 39 of the head cage 240, causing compression of the packing element 347 into sealing engagement with the casing. Simultaneously, the upper slips 25 will ratchet downwardly with some degree of compression in the slip take-up spring 328 due to contact between the slip take-up ring 327 and the outwardly extending flange 320 of the setting sleeve 316. This downward ratcheting of the upper slip assembly will keep the upper slips 25 in position for immediate anchoring engagement of the teeth thereon with the casing when downward movement ceases, or is reversed.

Simultaneously with the above described movement, the gudgeon pin 74 has assumed a position at or above the position 74d in the I-slot profile 313 and the I-slot body 311 can be rotated to locate the pin 74 in the position 74e in I-slot profile 313. In this position further expanding force on the packing element 347 can be applied by upward motion of the mandrel 303, causing the gudgeon pin 74 to assume a position 74 thereby applying further compressive force to the packing element 347 by tension on the tubing string. However, if sufficient tubing weight is available, the tubing string can be lowered to further compress the packing element by placing the gudgeon pin 74 in position 74g whereby further compressive force on the packing element 347 can be applied through the upper connection 301, the setting sleeve 316, the head cage 240, the spacer collar 341 and upper thimble 343.

Also simultaneously with the above described setting movement, the mandrel seal 355, carried by the mandrel 303 enters the seal bore 351 of the packing sleeve 349, thereby effectively closing the commuincation passageway consisting of the ports 57 in the lower head 56, the entire area of the bore of 351 in the packing sleeve 349 and the ports 342 in the spacer collar 341.

By proper rotation of the J-slot profile 313, and upward movement of the J-slo-t body 311, the gudgeon pin 74 can be placed in position 74h or 741'. During such upward motion of the mandrel 303 the mandrel seal assembly 355 moves clear of the sealing bore 351 in the packing sleeve 349, re-esta-blishing communication from below the packing element 347 through the ports 57, through the space between the inwardly lower head 56 in the extended portion 354 of the lower thimble 352 and the mandrel 303 through the sealing bore 351 of the packing sleeve 349, outwardly through the ports 342 of the spacer collar 341 to the annulus between the tubing and easing above the packing element 347. The gudgeon pin 74 will assume the position 74h if compressive forces exist in the tubing string or the position 74i if tensile forces exist in the tubing string above the packer.

The by-pass communication through the packer can be reclosed by proper rotation and lowering of the mandrel 303 to cause the gudgeon pin 74 to reassume either the position 74g or 74f, which positions are determined by the existence of either compressive forces or tensile forces in the tubing string above the packer.

During either the opening or closing actions of the packer by-pass, described above, the packer remains in a set condition with the sealing element 347 in sealing engagement with the casing.

For retrieval, the tubing string, mandrel and J-slot body 311 are rotated and manipulated to place the gudgeon pin 74 in position 74a or 74b, and the tubing string is picked up. When the tubular string is picked up, the shoulder 306 on the mandrel 303 engages and picks up the setting sleeve 316 which, in turn, picks up the slip rest 324, the upper slip housing 26 and the upper slips 25 by engagement of the pickup pin 330 in the slot 322 of the setting sleeve 316. This action pulls the setting sleeve 316 from underneath the head segments 33 which are now free to collapse under urging of the head segment spring 34 and the upper slips 25 are pulled free from the head segments 33 and are free to collapse under the urging of the slip springs 24. The outwardly extended portion 8 on the mandrel 303 then contacts the inwardly extended portion 39 of the head cage 240 and thereby picks up the head cage, the spacer collar 341, upper thimble 343, packing sleeve 349, lower thimble 352 and the lower head 56, re-establishing the gap between the surface 61 of said lower head 56 and the surfaces 63 in the lower slips 62. In such extended position, the packing element 347 is free to relax out of sealing engagement with the casing. The inner seal assembly, consisting of the mandrel seal 355 is picked up by the snap ring 50 on the mandrel 303 and moved out of sealing engagement with the seal bore 351 of the packing sleeve 349. This movement re-establishes the bypass through the packer, as described hereinbefore.

It will be observed that in all forms described above the force generated by pressure from both above and below the set packer acts across the mandrel seal and is transferred by the mandrel to the upper and lower anchors through the resilient packer to thereby compensate for variations in pressure above and below the packer.

It will be understood that other and further forms of our invention may be made without departing from the spirit and scope of the appended claims.

Having described our invention we claim:

1. In a well packer, including: a packer assembly; upper and lower slip and slip expander members on the packer assembly; said upper expander members comprising a plurality of separate segments with said upper slips contacting outer surfaces thereon; a mandrel extending through said packer assembly; releasable attachment means between said mandrel and said packer assembly, whereby said mandrel can be disengaged from said packer assembly and moved axially with relationship thereto; a tubular setting sleeve slidably disposed upon said mandrel and arranged to be moved downwardly with said mandrel to contact said segments to move said segments outwardly to expand said slips; spring means to resiliently urge said segments and upper slips downwardly; a packer support sleeve carried by said packer assembly in spaced relationship to said mandrel; port means above and below said packer support sleeve providing a by-pass between said packer support sleeve and said mandrel; and seal means carried by said mandrel arranged to be moved with said mandrel into sealing engagement with the bore of said packer sleeve to close the by-pass when the packer is set.

2. In a well packer arranged to be set in a well casing, a tubular mandrel; a packer assembly including, a tubular body surrounding the mandrel in spaced relationship thereto; upper anchoring means including, expansible slips above the tubular body, and lower anchoring means including expansible slips below the tubular body; releasable attachment means between the packer assembly and the mandrel; a setting sleeve carried by the mandrel above the upper slips; a plurality of expander segments surrounding the mandrel behind the upper slips, the lower end of the setting sleeve being arranged to engage and move outwardly the expander segments; co-acting tapered surfaces on the expander segments and upper slips arranged to move the slips outwardly into anchoring engagement with the well casing; a lower expander head suspended to the tubular body arranged to be moved into engagement with the lower anchoring means to expand same outwardly; packing means slidably carried about the tubular body arranged to be expanded into sealing engagement with a surrounding casing; said setting sleeve being arranged to move downwardly with the mandrel when the mandrel is disengaged from the packer assembly; port means above and below the packing means communicating with the bore of the tubular body providing a by-pass passage between the mandrel and the tubular body; and seal means carried about the mandrel movable into the bore of the tubular body to close the by-pass passage when the mandrel is disengaged and moved with relation to the packer assembly.

3. The combination called for in claim 2 with the addition of piston means in the tubular body above the seal means on the mandrel arranged to exert downward force upon the seal means in response to pressure from above the packer after the packer is set.

4. The combination called for in claim 2 wherein the seal means includes a seal element on the lower face thereof arranged to seal against a sealing surface projecting from the inner side of the by-pass passage which seal element is pressed downwardly against the said sealing surface by pressure from below the packer after it is set.

5. The combination called for in claim 2 wherein the means for releasably attaching the mandrel to the packing assembly comprises a co-operating J-slot and gudgeon pin connection located below the lower anchoring slips.

6. The combination called for in claim 5 wherein the .T-slot includes an upwardly facing surface and a downwardly facing surface whereby force can be exerted against the gudgeon pin in two directions.

7. The combination called for in claim 5 wherein the J-slot includes spaced downwardly facing and upwardly facing surfaces at the upper and lower ends thereof and upwardly and downwardly facing surfaces intermediate the first mentioned upwardly and downwardly facing surfaces whereby the gudgeon pin may be moved to said intermediate surfaces to permit the by-pass to be opened and closed while the packer is set.

8. The combination called for in claim 5 wherein the J-slot is C shaped whereby it can be reversed to reverse the required rotation of the tubing string to engage and disengage the mandrel from the packer assembly.

(References on following page) 15 References Cited 3,329,210 7/1967 3,338,308 8/1967 UNITED STATES PATENTS 3,352,362 11/1967 9/1964 Clark et a1 166129 3 356 142 12 19 7 3/1953 Fitzpatrick 166-134 5 6/1954 Baker et a1. 166-129 12/1963 Keithahn 166-134 X 5/1966 McGowan 166-134 X 10/1966 Grimmer 166-130 X 166-134, 140

Brown 166-129 Elliston et a1. 166-134 X Lebourg 166-140 Crow et a1. 166-134 DAVID H. BROWN, Primary Examiner.

US. Cl. X.R. 

